1. Field of the Invention
The present invention relates to an apparatus front panel with a mechanical user interface in the form of mechanically controllable regulation and setting elements on the face of the front panel.
2. Description of the Prior Art
It is often necessary to alter the appearance of the apparatus front panel, e.g. the language of a text on the front panel, indicates associated with scales or dials, or to carry out other changes, e.g. as a result of a changed function in the apparatus. Heretofore, this problem has been solved by exchanging the front panel and the associated electronics, displays and control means. This has the disadvantage that a number of different front panels has to be kept in reserve for a single apparatus.
Touch screens, having several different transparent layers on which conductive patterns are printed, are known. The layers are touch-sensitive in such a way that the impedance in the conductive pattern is altered upon pressure or upon touching the layer on the screen, and this change in impedance is used to call up various functions in an associated computer. German OS 34 09 532, U.S. Pat. Nos. 4,653,086 and 4,566,001 describe such devices, in which resistive changes upon touching the touch-sensitive layers are used, and German OS 32 30 919 describes a technique in which capacitive changes arising upon touching are used to control a display device. These known techniques are suited in particular for applications in which the user has to choose between a number of information images, as in menu selection, process control in the field of industry, different instruments, etc.